Rudbeckia plant named ‘RUDFA538’

ABSTRACT

A new cultivar of Rudbeckia plant named ‘RUDFA538’ that is characterized by its vigorous growth habit, yet compact plant habit, its inflorescences with an average of 4 whorls of ray florets, its very floriferous blooming habit, and its inflorescences with ray florets that are grey-yellow to yellow when opening and changes to grey-purple to grey-orange when fully open.

Botanical classification: Rudbeckia hirta.

Variety denomination: ‘RUDFA538’.

CROSS REFERENCE TO A RELATED APPLICATION

This application claims priority to European Community Plant VarietyOffice (CPVO) Plant Breeder's Rights Application No. 2020/0016 filed onJan. 6, 2020 under 35 U.S.C. 119(f), the entire contents of which isincorporated by reference herein.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar ofRudbeckia hirta and will hereafter by referred to by its cultivar name,‘RUDFA538’. The new cultivar is an herbaceous perennial grown for use asa landscape plant.

‘RUDFA538’ was derived from a breeding program conducted by the Inventorat a nursery in Zuidwolde, The Netherlands. The objective of thebreeding program was to select new cultivars of Rudbeckia withfloriferous blooming habits and compact plant habits.

‘RUDFA538’ was selected in July of 2018 by the Inventor from amongstseedlings in a trial field that had been planted with seed derived fromopen pollination of numerous unpatented and unnamed proprietary plantsfrom the Inventor's breeding program in July of 2017. The exactparentage is therefore unknown.

Asexual propagation of the new cultivar was first accomplished under thedirection of the Inventor by tissue culture using meristematic tissue inHeerhugowaard, The Netherlands in March of 2019. Asexual propagation bytissue culture has determined that the characteristics of the newcultivar are stable and are reproduced true to type in successivegenerations.

STATEMENT REGARDING PRIOR DISCLOSURES BY THE INVENTOR

The Applicant asserts that no publications or advertisements relating tosales, offers for sale, or public distribution occurred more than oneyear prior to the effective filing date of this application. Anyinformation about the claimed plant would have been obtained from adirect or indirect disclosure from the Inventor. The Applicant claims aprior art exemption under 35 U.S.C. 102(b)(1) for disclosure and/orsales prior to the filing date but less than one year prior to theeffective filing date. Disclosures includes but may not be limited to awebsite listing by AB-Cultivars (a company owned by the Inventor).

SUMMARY OF THE INVENTION

The following traits have been repeatedly observed and represent thecharacteristics of the new cultivar. These attributes in combinationdistinguish ‘RUDFA538’ as a unique cultivar of Rudbeckia.

-   -   1. ‘RUDFA538’ exhibits a vigorous growth habit, yet compact        plant habit.    -   2. ‘RUDFA538’ exhibits inflorescences with an average of 4        whorls of ray florets.    -   3. ‘RUDFA538’ exhibits a very floriferous blooming habit.    -   4. ‘RUDFA538’ exhibits inflorescences with ray florets that are        grey-yellow to yellow when opening and changes to grey-purple to        grey-orange when fully open.

‘RUDFA538’ can be compared to the Rudbeckia cultivars ‘Sahara’ (notpatented), and ‘Maya’ (not patented). ‘Sahara’ and ‘Maya’ are bothsimilar to ‘RUDFA538’ in plant height and in having multiple rows of rayflorets. ‘Sahara’ differs from ‘RUDFA538’ in having ray florets that arecoppery orange in color throughout the entire flowering season. ‘Maya’differs from ‘RUDFA538’ in having ray florets that are deep yellow incolor throughout the entire flowering season.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying colored photographs illustrate the overall appearanceand distinct characteristics of the new Rudbeckia. The photographs weretaken of a 5.5-month-old plant of ‘RUDFA538’ as grown outdoors in a17-cm container in Zuidwolde, The Netherlands.

The photograph in FIG. 1 is a side view of ‘RUDFA538’ in bloom.

The photograph in FIG. 2 provides a close-up view of the younginflorescences of ‘RUDFA538’.

The photograph in FIG. 3 provides a close-up view of the matureinflorescences of ‘RUDFA538’.

The photograph in FIG. 4 provides a close-up view of the foliage of‘RUDFA538’.

The colors in the photographs are as close as possible with thephotographic and printing technology utilized and the color values citedin the detailed botanical description accurately describe the colors ofthe new Rudbeckia.

BOTANICAL DESCRIPTION OF THE PLANT

The following is a detailed description of 5.5-month-old plants of‘RUDFA538’ as grown outdoors in 17-cm containers in Zuidwolde, TheNetherlands. The phenotype of the new cultivar may vary with variationsin environmental, climatic, and cultural conditions, as it has not beentested under all possible environmental conditions. The colordetermination is in accordance with The 2015 Colour Chart of The RoyalHorticultural Society, London, England, except where general color termsof ordinary dictionary significance are used.

-   General description:    -   -   Blooming period.—Average of 13 weeks from early summer to            late summer in The Netherlands.        -   Plant type.—Perennial.        -   Plant habit.—Upright, compact.        -   Plain shape.—Narrow obovate.        -   Height and spread.—Average of 56 cm in height from soil            level to top of foliar plane and 60 cm in height from soil            level to top of floral plane, 50.8 cm in diameter.        -   Hardiness.—At least in U.S.D.A. Zones 4 to 10.        -   Diseases and pests.—No susceptibility and resistance to            diseases or pests has been observed.        -   Root description.—Fine and fibrous.        -   Propagation.—Tissue culture.        -   Root development.—An average of 3 weeks for root initiation            with a young rooted plant produced in an average of 6 weeks.        -   Growth rate and vigor.—Vigorous, yet compact.-   Stem description:    -   -   Shape.—Moderately angled.        -   Stem color.—Young stems; 146C, N77A to N77B at the angles.            mature stems; 143B, N186C at the angles.        -   Stem size.—An average of 5.5 mm in diameter and an average            of 29.4 cm in height.        -   Stem surface.—Moderately glossy and densely covered with            strigose hairs an average of 2 mm in length and close to            155A in color.        -   Stem number.—Average of 11 main stems, 4 lateral branches            per main stem.        -   Internode length.—An average of 3.2 cm in length.        -   Stem aspect.—Main stems; average of 15° to vertical, lateral            branches; average of 20° to main stems.        -   Branching.—Freely branching from base with lateral stems.-   Foliage description:    -   -   Leaf shape.—Broadly ovate.        -   Leaf division.—Simple.        -   Leaf base.—Cuneate.        -   Leaf apex.—Acute.        -   Leaf venation.—Pinnate, color upper surface 145A, color            lower surface 146C.        -   Leaf margins.—Coarsely serrate, coarsely and very slightly            undulate.        -   Leaf attachment.—Petiolate.        -   Leaf arrangement.—Alternate.        -   Leaf size.—Average of 10.6 cm in length and 3.9 cm in width.        -   Leaf color.—Young upper surface; 137B, young lower surface;            138A, mature upper surface: NN137A, mature lower surface;            147B.        -   Leaf surface.—Upper surface matte, and non-rugose, rough to            touch, lower surface is matte, slightly rugose, rough to            touch, both surfaces densely pubescent with short strigose            hairs; an average of 1.5 mm in length and N155D in color.        -   Petioles.—Average of 1.9 cm in length, flattened, average            diameter at widest point 1.1 cm and at narrowest point 4 mm,            upper surface color; 145A with margins NN137B, lower surface            color; 146A to 146B with margins 147B, both surfaces            slightly glossy and densely covered with strigose hairs; an            average of 1.5 mm in length and N155D in color.-   Flower description:    -   -   Type.—Terminal capitulum, consisting of ray florets and disk            florets.        -   Capitulum number.—5 per stem, up to 75 per plant.        -   Lastingness of inflorescence.—Average of 2 weeks,            persistent.        -   Capitulum size.—Matures to about 6.3 cm in height and 9.3 cm            in diameter, disk size is an average of 2.8 cm in diameter.        -   Fragrance.—None.        -   Involucral bracts (phyllaries).—Cuneate base, acute apex,            narrow ovate to narrow elliptic in shape, entire margins,            average of 42 arranged in two rows, 3.3 cm in length and 9            mm in width, color; upper surface when fully open NN137A,            lower surface when fully open 138A, both surfaces and            margins matte and densely covered with strigose hairs; an            average of 1.5 mm in length and NN155D in color.        -   Receptacle.—Near orbicular in shape, an average of 1 cm in            height and diameter, 157D in color.        -   Buds.—Globular in shape, immature ray florets pointed upward            and curling inward, up to 2 cm in length and 5.1 cm in            diameter, immature ray florets are 151D in color, immature            involucral bracts upper surface NN137A, lower surface 138A,            surface on involucral bracts and immature ray florets is            densely covered with strigose hairs; an average of 1.5 mm in            length and NN155D in color.        -   Peduncle.—Strong, straight on top of main flowering stem,            average of 7.2 cm in length and 6 mm in diameter, color:            145B and axially striped 143B, surface moderately glossy            sand densely covered with short strigose hairs; an average            of 2 mm in length and NN155D in color.        -   Ray florets.—Average of 100, rotate around the disk, oblong            in shape, average of 4.2 cm in length and 1.3 cm in width,            emarginate apex, cuneate base, entire margin, both surfaces            are velvety, matte and glabrous, held near horizontal,            color; when opening upper surface; lower ⅓^(rd) 185A, upper            ⅔^(rd) 11A, when opening lower surface; lower ⅔^(rd) 160A to            160B, upper ⅓^(rd) 1B, when fully open upper surface and            veins; lower ⅔^(rd) 187B, upper ⅓^(rd) 174D, when fully open            lower surface; 177C, flushed with 184D, veins N144A.        -   Disk flowers.—Average of 800, tubular, 20 whorls arranged            spirally on a conical receptacle, lower 90% fused into tube,            upper 10% free, about 8 mm in length and 3 mm in width, free            lobes have entire margins and are curled backwards, both            surfaces glabrous and moderately glossy, color; when opening            and fully open upper and lower surface 200A and 203A,            changing to 159C at the base, spines; none, bracts. — 1 per            disk floret, spirally placed on disk, soft, flattened, an            average of 7 mm in length and 1 mm in diameter, oblanceolate            in shape, acute apex, narrow cuneate base, color apex;            N186C, color mid-section and base; NN155B, color margins;            N186C.-   Reproductive organs:    -   -   Gynoecium.—Pistil; 1, 7 mm in length, style; 5 mm in length,            color; 200A, mid-section and base 158D, stigma; cleft,            decurrent, 3 mm in diameter, 203A in color, ovary; 155C in            color.        -   Androecium.—Stamens; 5, filaments; 2.5 mm in length, 158D in            color, anther; narrow oblong in shape, 2.5 mm in length, 0.5            mm in width, 200A and 203A in color, pollen; moderate in            quantity and 17B in color.        -   Fruit/seed.—None observed to date.

It is claimed:
 1. A new and distinct cultivar of Rudbeckia plant named‘RUDFA538’ substantially as herein illustrated and described.